1. Field of the Invention
The invention relates to a unitary lighting unit for the exterior mirror of a vehicle. More particularly, the invention relates to a unitary lighting unit, whereby a part of the lighting unit corresponds to an indicator, while another part of the lighting serves as a warning display for assistance systems.
2. Description of the Related Art
Conventional exterior mirrors have a design allowing the mirror head to be folded backwards in relation to the mirror base, by hand or driven by a motor, in a direction rearwards with respect to the direction of movement of the vehicle. In addition, the mirror glass bracket can normally be positioned in the mirror head from the inside of the vehicle. A perfect view is thus ensured for the driver, which results in better road safety. Many exterior mirrors comprise an indicator, e.g., a turn signal, which is provided on the front side of the mirror housing in the direction of movement. For road users who are next to or behind the exterior mirror, the indicator can generally not be seen, or only insufficiently. Therefore, additional LEDs are incorporated into the mirror design, which radiate against the direction of travel, and are integrated on the outermost edge of the exterior mirror in the indicator.
According to ECE regulations, an additional turn signal light in the exterior mirror should light up a region beginning from 5° from the longitudinal axis of the vehicle, up to 60° to the longitudinal axis of the vehicle in the opposite direction of movement.
A variety of solutions for indicators in the exterior rear view mirror is known from the related art. Indicator modules are integrated into the housing of an exterior mirror in the process. According to the design, these indicator modules contain optical fibers, reflectors, printed circuit boards, lenses and cover glass and illuminants. LEDs are increasingly used as illuminants due to the known advantages.
An embodiment is known in EP 0 858 932 A2. In this embodiment, an indicator module is formed, which comprises a light conductor. The light conductor forms a constant contour with the housing of an exterior mirror. The light of an LED is coupled at one end of the light conductor and transported over the whole length. The emission of the light takes place over the whole length of the light conductor, depending on the thickness of the decoupling devices and at the end of the light conductor. It has been shown that this solution is not sufficient for the optimal lighting of a lighting device. The desired light intensity is not achieved with the solution of the distant coupling of light and the transport of 5 to 20 cm.
A lighting unit is known in U.S. Pat. No. 7,357,549, which includes light conductor elements, into which at least one LED protrudes. In this embodiment, a light conductor is divided into several sections and includes a recess along its longitudinal extension. Due to the recess in the light conductor, the latter is weakened in its stability, and/or the external constant surface of the light conductor is disturbed by an elevation. Due to the light conducting material being optically clear, the light coupling point is visible from the outside, which distorts the harmonious impression of the light conductor.
U.S. Pat. No. 7,255,464, discusses a variety of embodiments of light modules. This reference does not, however, discuss the combination of two lighting units in one module. In this publication, no emission of light of a warning display on the vehicle side in the mirror housing is described.
Furthermore, solutions for displaying a hazardous situation are known in the related art, which are installed on and/or in the exterior mirror of a vehicle. Warning displays must be installed in such a way that they are noticed by the driver of the vehicle when they light up. A position on the inner housing cover of the exterior mirror is therefore appropriate.
Modules are known for these types of warning displays, which are controlled by an assistance system and light up in reaction to a control signal. An example is U.S. Pat. No. 7,492,281, which shows the use of a warning display in the housing cover. The warning display is designed as an independent module, and is mounted into the mirror head separately from other lighting devices.
All lighting elements known in the prior art for various functions of the exterior mirror are designed as individual components and are integrated into the openings provided for them.